EP2858810A1 - Structure composite ayant un noyau à faible masse volumique et un renforcement de couture composite - Google Patents

Structure composite ayant un noyau à faible masse volumique et un renforcement de couture composite

Info

Publication number
EP2858810A1
EP2858810A1 EP13729177.9A EP13729177A EP2858810A1 EP 2858810 A1 EP2858810 A1 EP 2858810A1 EP 13729177 A EP13729177 A EP 13729177A EP 2858810 A1 EP2858810 A1 EP 2858810A1
Authority
EP
European Patent Office
Prior art keywords
core
fibers
composite layup
density
composite
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP13729177.9A
Other languages
German (de)
English (en)
Inventor
Nicholas Joseph Kray
Wendy Wen-Ling Lin
Dong-Jin Shim
Ross SPOONIRE
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co
Original Assignee
General Electric Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by General Electric Co filed Critical General Electric Co
Publication of EP2858810A1 publication Critical patent/EP2858810A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/06—Fibrous reinforcements only
    • B29C70/08—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/06—Fibrous reinforcements only
    • B29C70/08—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers
    • B29C70/086—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers and with one or more layers of pure plastics material, e.g. foam layers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/06—Fibrous reinforcements only
    • B29C70/10—Fibrous reinforcements only characterised by the structure of fibrous reinforcements, e.g. hollow fibres
    • B29C70/16—Fibrous reinforcements only characterised by the structure of fibrous reinforcements, e.g. hollow fibres using fibres of substantial or continuous length
    • B29C70/24—Fibrous reinforcements only characterised by the structure of fibrous reinforcements, e.g. hollow fibres using fibres of substantial or continuous length oriented in at least three directions forming a three dimensional structure
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/68—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts by incorporating or moulding on preformed parts, e.g. inserts or layers, e.g. foam blocks
    • B29C70/86—Incorporated in coherent impregnated reinforcing layers, e.g. by winding
    • B29C70/865—Incorporated in coherent impregnated reinforcing layers, e.g. by winding completely encapsulated
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
    • B29D99/00—Subject matter not provided for in other groups of this subclass
    • B29D99/001—Producing wall or panel-like structures, e.g. for hulls, fuselages, or buildings
    • B29D99/0021—Producing wall or panel-like structures, e.g. for hulls, fuselages, or buildings provided with plain or filled structures, e.g. cores, placed between two or more plates or sheets, e.g. in a matrix
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/02—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by structural features of a fibrous or filamentary layer
    • B32B5/06—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by structural features of a fibrous or filamentary layer characterised by a fibrous or filamentary layer mechanically connected, e.g. by needling to another layer, e.g. of fibres, of paper
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2063/00—Use of EP, i.e. epoxy resins or derivatives thereof, as moulding material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2307/00—Use of elements other than metals as reinforcement
    • B29K2307/04—Carbon
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2031/00—Other particular articles
    • B29L2031/08—Blades for rotors, stators, fans, turbines or the like, e.g. screw propellers
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/23—Sheet including cover or casing
    • Y10T428/233—Foamed or expanded material encased
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/23—Sheet including cover or casing
    • Y10T428/239—Complete cover or casing

Definitions

  • This invention relates generally to composite structures, and more particularly to composite gas turbine engine fan blades.
  • Composite wide-chord fan blades are known for use in gas turbine engines.
  • a large engine having all-composite wide chord fan blades offers a significant weight savings over a large engine having fan blades made from metal alloys.
  • a composite structure includes: a core having a pair of opposed exterior surfaces and having a first density; a composite layup surrounding the core, the composite layup comprising a plurality of layers of fibers embedded in a matrix and extending along the exterior surfaces of the core, the composite layup having a second density; and stitching comprising fibers extending through the core and at least a portion of the composite layup.
  • a method of making a composite structure includes: stitching fibers through both of: a core that includes a pair of opposed exterior surfaces, wherein the core has a first density; and at least a portion of a composite layup that surrounds the core, the composite layup comprising a plurality of layers of fibers extending along the exterior surfaces of the core, the fibers embedded in an uncured resin matrix, wherein the composite layup has a second density; and simultaneously curing the core, the composite layup, and the fibers.
  • Figure 1 is a schematic side view of a turbine engine fan blade constructed in accordance with an aspect of the present invention
  • FIG. 2 is a view taken along lines 2-2 of FIG.1;
  • FIG. 3 an enlarged view of a portion of FIG. 2.
  • FIG. 1 illustrates an exemplary composite fan blade 10 for a high bypass ratio turbofan engine (not shown) including a composite airfoil 12 extending in a chordwise direction C from a leading edge 16 to a trailing edge 18.
  • the airfoil 12 extends radially outward in a spanwise direction S from a root 20 to a tip 22.
  • the airfoil 12 has a concave pressure side 24 and a convex suction side 26.
  • the airfoil 12 is constructed from a composite layup 28 with a core 30 disposed therein.
  • composite refers generally to a material containing a reinforcement such as fibers or particles supported in a binder or matrix material.
  • the composite layup 28 includes a number of layers or plies 32 embedded in a matrix and oriented substantially parallel to the pressure and suction sides 24 and 26.
  • a nonlimiting example of a suitable material is a carbonaceous (e.g. graphite) fiber embedded in a resin material such as epoxy. These are commercially available as fibers unidirectionally aligned into a tape that is impregnated with a resin.
  • prepreg Such "prepreg” tape can be formed into a part shape, and cured via an autoclaving process or press molding to form a light weight, stiff, relatively homogeneous article.
  • the core 30 has a cambered airfoil shape which generally follows the shape of the airfoil 12 and is bounded by opposed concave and convex exterior surfaces 34 and 36, respectively.
  • the core 30 comprises a low-density material such as polymeric foam.
  • low-density does not refer to any absolute magnitude, but rather the relative density of the core 30 compared to that of the composite layup 28.
  • a suitable core material is an elastomeric polyurethane foam having a density of about 40% of the density of the composite layup 28.
  • reinforcing fibers 38 are stitched through the core 30 and through at least part of the composite layup 28.
  • the fibers 38 may be formed using any fiber with a high tensile strength.
  • the fibers 38 comprise tows of intermediate modulus carbon fiber, similar to the fibers used to manufacture the tapes described above.
  • Another example of a suitable material is carbon nanofiber.
  • the fibers 38 are configured in a continuous pattern including transverse fibers 40 extending transverse to the core exterior surfaces 34 and 36, (i.e. in a through- thickness direction), interconnected by loops 42 extending parallel to the core exterior surfaces 34 and 36.
  • the fibers 38 may be configured as a series of side-by-side rows (one row 44 is depicted in front of another row 46 in FIG. 3), or in another two-dimensional or three-dimensional pattern.
  • the fibers 38 may be stitched using an ultrasonic needle apparatus.
  • the transverse fibers 40 extend through the core 30 and through at least a portion of the thickness of the composite layup 28.
  • the stitching can be done at a foam subcomponent level, in which case opposed "facesheets" 48 and 50 of composite material are first secured by the fibers 38 to the core outer surfaces 34 and 36. The subassembly would then be ready to assemble to the remainder of the airfoil 12.
  • the fibers 38 may be stitched through the composite layup 28 and the core 30 with the core 30 already assembled into the uncured composite layup 28.
  • the stitched fibers 38 When cured, the stitched fibers 38 add shear, compressive, and tensile strength to an otherwise low density, low strength material. In addition, the stitching increases the core's stiffness to decrease peak stresses in the composite caused by the core geometry. Optimization of the spacing between transverse fibers 40 (i.e. stitch pattern density) may be based on bulk analysis and/or coupon level testing.
  • the direction of the transverse fibers 40 relative to the outer surfaces 34 and 36 of the core 30 may be selected so as to provide the maximum shear loading capability at the carbon/foam interface.
  • the transverse fibers 40 are oriented with an angle a of approximately 45 degrees from perpendicular to the exterior surfaces 34 and 36.
  • the stitching (whether done at the core subassembly or airfoil assembly level) may be applied in a dry condition, with no composite resin used.
  • the entire airfoil 12 may be then be cured using a known autoclave process. During the cure, resin from the matrix of the composite layup 28 is free to wick along the fibers 38, and cure in place, incorporating the fibers 38 as part of the cured structure.
  • the reinforcing structure and process described herein enables the use of low- density foam in a composite airfoil. This process adds strength and decreases stress concentrations with the minimum amount of weight. It is an enabler for low density foam application in fan blades. This has a ripple effect into disk, case, and attachment hardware. Being able to use this foam will provide a technical advantage over solid composites.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Textile Engineering (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Moulding By Coating Moulds (AREA)
  • Laminated Bodies (AREA)

Abstract

La présente invention concerne une structure composite qui comprend : un noyau ayant une paire de surfaces extérieures opposées et ayant une première masse volumique ; une enveloppe composite entourant le noyau, l'enveloppe composite comprenant une pluralité de couches de fibres intégrées dans une matrice et s'étendant le long des surfaces extérieures du noyau, l'enveloppe composite ayant une deuxième masse volumique ; et une couture comprenant des fibres s'étendant à travers le noyau et au moins une partie de l'enveloppe composite.
EP13729177.9A 2012-06-06 2013-05-31 Structure composite ayant un noyau à faible masse volumique et un renforcement de couture composite Withdrawn EP2858810A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US13/490,235 US20130330496A1 (en) 2012-06-06 2012-06-06 Composite structure with low density core and composite stitching reinforcement
PCT/US2013/043510 WO2013184491A1 (fr) 2012-06-06 2013-05-31 Structure composite ayant un noyau à faible masse volumique et un renforcement de couture composite

Publications (1)

Publication Number Publication Date
EP2858810A1 true EP2858810A1 (fr) 2015-04-15

Family

ID=48626642

Family Applications (1)

Application Number Title Priority Date Filing Date
EP13729177.9A Withdrawn EP2858810A1 (fr) 2012-06-06 2013-05-31 Structure composite ayant un noyau à faible masse volumique et un renforcement de couture composite

Country Status (7)

Country Link
US (1) US20130330496A1 (fr)
EP (1) EP2858810A1 (fr)
JP (1) JP2015525155A (fr)
CN (1) CN104349888A (fr)
BR (1) BR112014030596A2 (fr)
CA (1) CA2875029A1 (fr)
WO (1) WO2013184491A1 (fr)

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EP3237510B1 (fr) * 2014-12-22 2023-07-26 Basf Se Éléments moulés renforcés à l'aide de fibres en mousse particulaire expansée
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JP6672233B2 (ja) * 2017-09-25 2020-03-25 三菱重工業株式会社 複合材翼の成形方法、複合材翼及び複合材翼の成形型
US11931981B2 (en) 2018-01-29 2024-03-19 General Electric Company Reinforced composite blade and method of making a blade
JP6738850B2 (ja) * 2018-03-29 2020-08-12 三菱重工業株式会社 複合材料翼および複合材料翼の製造方法
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Also Published As

Publication number Publication date
US20130330496A1 (en) 2013-12-12
WO2013184491A1 (fr) 2013-12-12
BR112014030596A2 (pt) 2017-06-27
CN104349888A (zh) 2015-02-11
JP2015525155A (ja) 2015-09-03
CA2875029A1 (fr) 2013-12-12

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